latter half of microbio

number of different species that inhabit the human host

800

organisms that forego ________ relationships can produce disease and pathogenic response

Symbiotic

classifications of bacteria

Microscopic Morphology, Staining Charachteristics, Ability to Multiply, Drug Susceptibility Patterns, Antibody-based Serotyping

nucleic acid sequence and DNA homology, on nucleotide content, analysis of plasmid content, or ribotyping

Genetic Characterization

cells that do not have a nuclear membrane

Prokaryotic

T/F: bacteria do not have organelles

True

bacterial ribosomes ____ are made of the ____ and _____ subunits

70S; 30S and 50s

bacteria that possess a thick peptidoglycan layer surrounding the inner cytoplasmic membrane

Gram-Positive

bacteria that have a reduce peptidoglycan layer and instead of an outer membrane comprised of embedded core lipopolysaccharide and lipid A endotoxin

Gram-Negative

upon treatment with iodine, the bacteria loses its primary stain. this bacteria is gram-____________ (positive/negative)

Negative

lipopolysacchride on the membrane of gram-negative organisms binds to the ______ receptor on macrophages and endothelial cells and induces an immune response (secretion of interleukins, chemokines, and inflammatory cytokines)

CD14

T/F: a capsule containing antigenic proteins is found in both gram-positive and gram-negative cells

True

organisms capable of using CO2

Autotrophs

live under aerobic or anaerobic conditions

Facultative Organisms

restricted to the use of oxygen as the final electon acceptor

Obligate Aerobes

use the process of fermentation to live in the absence of molecular O2

Anaerobes

organisms that live on dead organic matter

Saprophytes

prevents pathogens by competing and stimulating the production of cross-protective antibodies against invading organisms

Normal Flora

may trigger pathological damage due to alterations in homeostasis

Stress, Malnutrition, and Immune Suppression

vitamins secreted in excess by the gastrointestinal tract to benefit the host

K and B12

physical barrier for Staphylococcus epidermis and Corynebacterium diphtheriae --> acne formation

Skin

washing hands limits the spread of both ______ and -____ bacteria

Commensal and Pathogenic

commonly captures organisms in the mucosal layer, with subsequent clearance by the cilia

Upper Respiratory Tract

requires macrophages and phagocytes to maintain a relative balance of bacterial cell numbers

Lower Respiratory Tract

commensal organisms of the normal body flora

Mouth, Stomach, Small Bowel, and Large Intestine

associated with vaginal epithelium and live in highly acidic conditions

Escherichia coli and Group B Streptococcus

colonizes the vaginal epithelium during childbearing years and helps establish the low pH that inhibits other pathogens

Lactobacillus acidophilus

amount of genes contained in single double-stranded supercoiled DNA chromosome

3000

self-replicating small, circular, non-chromosomal, double-stranded DNA molecules that may contain genes for antibiotic resistance and virulence factors

Plasmid

a virus that infects bacteria due to its protein coat that allows them to survive outside the bacterial host

Bacteriophages

highest efficiency of genetic exchange occurs within _______ (same/different) bacterial species

Same

naked DNA is taken up directly by recipient bacteria and is sometimes mediated by surface competence factors

Transformation

utilizes bacteriophages to mediate direct transfer of nucleic acids

Transduction

one-way transfer of plasmids by means of physical contact from F-positive bacterial cell to the F-negative bacterium

Conjugation

conjugation is often associated with _______ genes

Drug Resistance

depends on environmental conditions of the bacteria

Growth Phase

phase where bacteria adapt to growth conditions and are producing the substances needed for cell division

Lag Phase

phase when organisms are reproducing at their maximum rate

Exponential Phase

phase where depletion of nutrients and exhaustion of available resources halts reproduction

Stationary Phase

phase when bacteria run out of nutrients and die

Death Phase

enzymes that unwind the chromosome to allow proteins to bind and replicate the single strand of the DNA

Girases (Topoisomerases)

DNA replication always occurs in the ______ to _____ direction

5' to 3'

allow for the bidirectional copying of DNA fragments on the lagging strand which are later connected by ligases

Okazaki Fragments

precursor to full-blown sepsis and is caused by bacteria being found in the bloodstream

Systemic Inflammatory Response Syndrome

in severe septic states, organ perfusion is affected leading to ______ and ________

Hypoxia and Hypotension

multiple organ failure

Septic Shock

enterotoxins, toxic to the intestinal tract and causes vomiting and diarrhea

Exotoxins

considered a powerful endotoxin

LPS

two mechanisms for bacterial toxin action

Damage to Cellular Membranes and Inhibition of Protein Synthesis

________ in these antibiotics that target the cell wall attach to enzymes from that cross-link peptidoglycan and block cell wall synthesis

Beta-Lactam Rings

cell wall synthesis; inhibit peptidoglycan polymerization

Penicillin and Cephalosporins

inhibits synthesis of cell wall substrates; cell wall synthesis

Vancomycin

interfere with ribosome function through binding to the 30S or 50S ribosomal subunit

Aminoglycosides, Streptomycin, Tetracycline, Chloramphenicol, Erythromycin, Clarithromycin, Azithromycin, and Clindamycin

bind to a bacterial complex of DNA and DNA gyrase, blocking DNA replication

Quinolones

blocks transcription of mRNA synthesis by binding and inhibiting RNA polymerase

Rifampin

damage DNA

Nitroimidazoles

inhibit DNA unwinding needed for DNA synthesis

Nalidixic Acids (Floxacin, Ciprofloxacin, and Norfloxacin)

block the synthesis of folate needed for DNA replication

Sulfonamides and Trimethroprim

disrupt the plasma membrane causing leakage

Polymyxins and Amphotericin

the plasma membrane sterols of fungi are attacked by __________

Polyenes and Imidazoles

bacterial resistance mechanisms

Limited Entry, Change in Receptor, and Metabolic Inactivation

antimicrobial resistance

Spontaneous Mutation, Bacterial Transformation, and Plasmid Transfer

nonmotile, non-spore forming, gram-positive organisms that cause pyogenic and pyrogenic infections (pus and fever)

Gram-Postive Cocci

Staph infections are caused by several different types of staph germs including

MRSA (methicillin-resistant Staphylococcus aureus), MSSA (methicillin-susceptible Staphylococcus aureus), VISA (vancomycin-intermediate Staphylococcus aureus), and VRSA (vancomycin-resistance Staphylococcus aureus)

diseases of S. aureus

Folliculitis, Furuncles, Impetigo, Wounds, Bacteremia, Endocarditis, Pneumonia, and Osteomyelitis

rare infection caused by certain toxin-producing strains of Staphylococcus aureus infants, erythema followed by skin desquamation

Scalded Skin Syndrome (SSS)

rare and sometimes fatal staphylococcus infection that generally occurs in menstruating women, most of whom use vaginal tampons for menstrual protection

Toxic Shock Syndrome (TSS)

occurs 1-8 hours after toxic ingestion and last less then 24 hours

Food Poisoning

are normal inhabitants of the oral cavity and are a cause of transeint bactermia after dental procedures. In patients with pre-existing valvular lesions, viridans streptococci can adhere to fibrin-platelet aggregates through dextrans to establish infection that leads to endocarditis

Viridans streptococci

disease associated with Viridans streptococci

Endocarditis

an organism that lives on or in a host organism and gets its food from or at the expense of its host

Parasite

the single-celled microscopic animals, larger than viruses

Protozoa

multicellular parasitic organisms like nematodes and platyhelminths (trematodes, cestodes)

Helminths

parasites that live on the external surface of a host

Ectoparasites

neither benefit at expense of each other

Commensal Symbiotic

one member benefits at expense of other

Parasitic Symbiotic

both benefit from each other

Mutualistic Symbiotic

only live in association with host

Obligate Symbiotic

not essential for life or reproduction for one or both host and parasite

Facultative Symbiotic

T/F: parasitic diseases occur universally among people who live in poverty

True

the total number of deaths from the five leading causes of death from parasites; malaria, visceral leishmaniasis, schistosomiasis, chagas disease, ascariasis

755,400

infectious diseases that primarily affect the poorest regions of the world (many of which are located in the tropics) and have not been a priority for funding agencies, pharmaceutical companies, or global policymakers

Neglected Tropical Diseases (NTDs)

five parasitic infections targeted by CDC as priorities for public health action

Chagas Disease, Neurocysticercosis, Toxocariasis, Toxoplasmosis, and Trichomoniasis

move with whip-like appendage

Flagellates

move with pseudopodia

Amebae

nonmotile organisms that form spores

Sporozoa

leading cause of waterborne disease in the USA: transmitted by fecal-oral ingestion

Cryptosporidium spp

T/F: chlorination of pools can prevent the spread of Cryptosporidium spp.

False

cryptosporidium spp inhabit the ______ _________ __________ __________ of the GIT

Brush Border Mucosal Membrane

Cryptosporidium spp.

"""Poopy Water"""

causes amoebic dysentery and transmitted by ingestion of mature cysts from fecal-contaminated food, water, hands, or sex

Entamoeba histolytica

Entamoeba spp.

Bloody Diarrhea w/ Mucus

enteric, flagellated, binucleated, ventral disc for adhesion to intestines transmitted by ingestion of infection cysts in fecal-contaminated food or water

Giardia lamblia

giardia lamblia

"""Traveler's-Associated Diarrhea"""

"disease with watery, foul-smelling, large volume ""greasy""/fatty diarrhea (steatorrhea)"

Acute Giardiasis

disease with foul-smelling, fatty stools, periods of diarrhea alternation with constipation, steatorrhea, lactose intolerance, vitamin B12 and fat-soluble vitamin deficiencies (ADEK) no blood, pus, or mucus in the stool

Chronic Giardiasis

causes granulomatous amebic encephalitis (GAE) and keratitis transmitted by cuts in the skin and infection develops in skin, eye, or brain

Acanthamoeba spp.

granulomatous amebic encephalitis in immunocompromised individuals typically results in ________ and keratitis in immunocompromised individuals can lead to _________

Death and Blindness

"""brain eating"" thermophilic amoeba transmitted by entry into nasal passages during warm fresh or poorly chlorinated water-related activity"

Naegleria fowleri

causes malaria and is transmitted by the Anopheles mosquito during blood meal, congenitally, blood transfusions, organ transplantations, or sharing needles and syringes

Plasmodium spp.